Males caring for offspring is a good reproductive strategy

Mar 28, 2007

Caring fathers in the animal world aren’t necessarily at a disadvantage compared with those who abandon their offspring.

In many species, males may increase their reproductive success in either of two ways: by caring for their offspring, which enhances offspring survival, or by deserting and searching for additional mating opportunities. Which of these alternatives will evolve under a given set of circumstances can be analysed with mathematical models, according to new research from the University of Bristol, published today in the Royal Society journal Biology Letters.

Dr Lutz Fromhage and colleagues in the Centre for Behavioural Biology at Bristol University have devised a new model that refutes the view, put forward in earlier work, that increased reproductive success through male care is intrinsically less valuable than increased reproductive success through desertion.

Their model takes into account a number of factors surrounding caring and deserting males. For example, both male types may be equally susceptible to paternity loss or caring males may have a superior ability to defend their paternity, and a caring male may reduce its amount of care in response to being cuckolded, thus decreasing the survival chances of offspring fathered by deserters.

Dr Fromhage said: “Earlier work has suggested that any gain accrued to deserters through re-mating inflicts an exactly corresponding decrement on carers, and thus has a double impact on the relative reproductive success of the two male types. However, this double impact only arises if the male types occur with equal frequency and deserting males are maximally biased towards cuckolding caring males rather than other deserting males.

“Such an assumption is hard to justify biologically, especially since caring males may often be in a better position to defend their paternity. If the latter is true, then male care actually provides a twofold advantage and can be maintained despite high probabilities that deserting males achieve an extra-pair copulation.

“Our model thus rejects the view that a fitness gain achieved through male care is generally worth less than an alternative fitness gain through re-mating. This point is critical to the interpretation of past and future studies of parental care, sexual selection and the evolution of mating systems.”

Source: University of Bristol

Explore further: Honey bees use multiple genetic pathways to fight infections

add to favorites email to friend print save as pdf

Related Stories

Women still find it tough to reach the top in science

Mar 24, 2015

Women are playing an increasing role in science today but there are still barriers that can prevent them from achieving success comparable to their male colleagues. This feeds the argument that there is a ...

New technologies for getting the most out of semen

Mar 19, 2015

For in vitro fertilization and other assisted reproductive technologies, selecting the healthiest and best swimming sperm from a sample of semen can dramatically increase success. Microfluidics—micro-scale technologies ...

A thoroughly urban new millipede

Mar 19, 2015

A tiny new millipede has been found which is only known to occur within the city of Launceston, Tasmania, Australia.

Recommended for you

Flocks of starlings ride the wave to escape

7 hours ago

Why does it seem as if a dark band ripples through a flock of European starlings that are steering clear of a falcon or a hawk? It all lies in the birds' ability to quickly and repeatedly dip to one side to avoid being attacked. ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.